A conventional fixing device for vehicle doors includes two members, which are arranged on a vehicle body panel and a door panel such that an inclined surface of one of the members comes into contact with a corresponding inclined surface of the other one of the members when the vehicle door is closed. The fixing device is adapted to urge and press one of the members (a movable member) against the other one of the members (a fixed member). See, for example, Patent Document 1.
That is, using the force by which the members are pressed against each other, the vehicle door in the closed state is pressed in a direction crossing the opening and closing direction of the vehicle door, or, for example, against the hinge portion, which is the motion pivot of the door. In this manner, backlash of the vehicle door is restrained through a simple configuration.